F1 reverse warning light

I just completed an oil change of my car and now it is giving me the red "gearbox" light when I reverse with a long "beep" vs the usual short. The light only comes on when throttle is applied and the reverse still works fine. All the forward gears also work fine both in standard and race without any warning lights. The only different thing this time (it's been on the lift many times) was raising the back of the car to put the undertray back on. The car is a 360CS.
Any ideas?

 

Still trying to determine what is going on - it is not doing it as much - only when I put higher revs. If I push the throttle gently, the alarm or warning don't come on, and the normal beeping isn't on either... Any thoughts?

 

The CS doesn't have a lever - just a switch.

 

Well, I solved the reverse warning light issue. It's a really a silly thing that was causing the error (and my doing). I replaced a lightbulb in the brake light, in doing so I bent one of the contact in the connectors. This closed a circuit on the reverse light and threw the error.

 

Someone at the track mentioned the light being out which lead to the investigation and "duh!" moment. Interesting that it would send a warning on the F1....